Effective Single Photodynamic Treatment of Onychomycosis Using a Multifunctional Porphyrin Photosensitizer and Green Light.

Onychomycosis is predominantly caused by the dermatophytes , and The main treatment obstacle concerns low nail-plate drug permeability. antifungal photodynamic treatment (PDT) and nail penetration enhancing effectiveness have been proven for multifunctional photosensitizer 5,10,15-(4--methylpyridinium)-20-(4-(butyramido-methylcysteinyl)-hydroxyphenyl)-[21,23]-porphine trichloride (PORTHE). This study investigates single PORTHE green laser/LED PDT of varying degrees of onychomycoses in a human nail model. , , onychomycoses were induced on nail pieces at 28 °C (normal air) and 37 °C (6.4% CO₂) during 3 to 35 days and PDTs applied to the 37 °C infections. All dermatophytes showed increasingly nail plate invasion at 37 °C between 7 and 35 days; arthroconidia were observed after 35 days for and . Using 81 J/cm² (532 nm) 7-day onychomycoses were cured (92%) with 80 µM PORTHE (pH 8) after 24 h propylene glycol (PG, 40%) pre-treatment and 35-day onychomycoses (52%-67%) with 24 h PORTHE (40-80 µM)/40% PG treatment (pH 5). 28 J/cm² LED light (525 ± 37 nm) improved cure rates to 72%, 83% and 73% for, respectively, , and 35-day onychomycoses and to 100% after double PDT. Data indicate PDT relevance for onychomycosis.